1. Field of the Invention
The present invention relates to an electrical connector for electrically connecting an electronic package such as an integrated circuit (IC) chip with a circuit substrate such as a printed circuit board (PCB), and particularly to a land grid array connector adapted for receiving a land grid package (LGP) therein and electrically connecting the LGP with a PCB.
2. Description of the Prior Art
Land grid array (LGA) connector for electrically connecting a Land Grid Package (LGP) with a printed circuit board (PCB) is widely used in the field of electrical connectors. The LGA connector typically comprises an insulative housing, a stiffener defined around the housing, a clip pivotably engaged on one end of the stiffener, and a lever engaged on an opposite end of the stiffener for fastening the clip onto the housing. The LGP is clasped between the clip and the housing.
Referring to FIGS. 5–6, a conventional Land Grid Array (LGA) connector is illustrated. The LGA connector 6 comprises an insulative housing 61 mounted on a printed circuit board (not shown), a stiffener 62 defined around the housing 61, a metal clip 63 pivotably engaged on one end of the stiffener 62, and a lever 64 engaged on an opposite end of the stiffener 62 for fastening the clip 63 onto the housing 61. The housing 61 comprises a supporting portion 611 for supporting an LGP 7 and a mounting portion 612 for being mounted in the stiffener 62. The supporting portion 611 and the mounting portion 512 each have rectangular plane plate configuration with a plurality of sides. Each side of the supporting portion 611 extends beyond corresponding side of the mounting portion 612, and therefore steps 613 are formed between corresponding sides of the supporting portion 611 and the mounting portion 612. The clip 63 comprises a pair of clasping portions 631 in the middle thereof and a pair of hooks 632 in one end for engaging with the stiffener 62.
The stiffener 62 comprises a bottom plate 621 and a plurality of side walls 622 extending from the bottom plate 621. The bottom plate 621 defines a middle window and four connecting portions therearound. The bottom plate 621 and the side walls cooperatively define a room for receiving the LGP 7. The middle window receives the mounting portion 612, and the connecting portions around the middle window support the steps 613 of the housing 61. The stiffener 62 further comprises a lath 623 extending outside from one side wall 622.
The lever 64 comprises an operation lever 641 and a mounting lever 642. The mounting lever 642 comprises an arched pressing portion 6422 in the middle for pressing the clip 63.
In use, the clip 63 is first rotated to a vertical open position, and the LGP 7 is seated onto a predetermined position of the housing 61. Then the clip 63 is rotated to a horizontal close position. When the clip 63 is fittingly rested on LGP 7, the operation lever 641 is actuated, and the pressing portion 6422 presses a end of the clip 63. When the operation lever 641 is rotated to horizontal, the latch 623 locks the operation lever 641, and therefore the housing 61 and LGP 7 are fastened between the stiffener 62 and the clip 63.
Because the lever 64 presses down on the clip 63, and the clasping portions 631 of the clip 63 press down on the LGP 7, the lever 64 simultaneously pulls up the end of the stiffener 62 thereat to counterbalance the pressing forces. In addition, the hooks 632 of the clip 63 tend to pull up the opposite end of the stiffener 62 thereat, to counterbalance the pressing forces of the clasping portions 631 of the clip 63.
Generally, the force required for the clasping portions 631 of the clip 63 to firmly retain the LGP 7 thereunder is considerable. Accordingly, the pressing force applied by the lever 64 on the clip 63 is also considerable. The result is that the pulling up force of the lever 64 is considerable, and the pulling up force of the clip 63 is also considerable.
Said pulling up forces operate on the opposite ends of the stiffener 62 respectively, and the pressing forces of the clasping portions 631 operate to press a center portion of the LGP 7. The stiffener 62 is limited rigid, and the opposite ends of the stiffener 62 tend to bend upward. Because the supporting portion 611 is fixedly seated on the sides of the stiffener 62, the corresponding ends of the housing 61 is prone to bend upward alone with the bended end of the stiffener 62. That is, distortion of the housing 61 is occurred. The upshot is that firm and reliable electrical connection between the LGP 7 and the housing 61 is diminished.
In view of the above, a new LGA connector which overcomes the above-mentioned disadvantages is desired.